Tool carrier with by-pass



Sept. 4, 1962 E. B. LAGucKl Toor. CARRIER WITH BY-PAss V/NmvVV//J BY;14.200,42?? |s AGENT 2 Sheets-Sheet 2 Sept. 4, 1962 E. B. LAGUcKl TomdCARRIER WITH BY-PAss Filed July 25, 1960 mvENToR:

E. B. LAGUCKI am. H37

Hls AGENT FIG.5

ite States 3,532,3@2 Patented Sept. 4, 1962 tire 3,052,302 TUL CARREERWHH Bit-'PASS Edward 12. Laguclii, Houston, Tex., assigner to Shell @ilCompany, New York, NX., a corporation of Delaware Filed gully 25, 1951i,Ser. No. 45,036

6 Claims. (Cl. 16e-153) This invention relates to apparatus adapted tomove an object through a pipe and pertains more particularly to a toolcarrier adapted to move a tool, instrument, or other piece of equipmentthrough a pipe string for example through the owline and tubing stringof an oil well.

During the drilling, completion, servicing and/or reconditioning of oilwells many objects such as sections of tubular goods, strainers,bottomhole chokes, tools, surveying and logging instruments, etc., mayfrom time to time be introduced into and positioned at a predeterminedlevel within either the well tubing or the well casing. These objectsare either dropped in the well so that they fall to a predeterminedposition by gravity or they are lowered to the desired position on awire line, or they are pumped into position. In pumping a tool intoposition within an oil well, the tool is generally provided with apacker or Isealing means surrounding it of a diameter equal to that ofthe tubing string through which it is to be pumped. After putting thetool in the tubing string, a fluid is pumped down the tubing string inback of it, with the fluid already in the tubing or in the oil well4being circulated up the annular space between the tubing string and thewell casing.

In the event that it is desired to retrieve the tool from the bottom ofthe well and remove it from the well, the flow of fluid into a well maybe reversed so that the ilow enters the annular space between the wellcasing and the Well tubing, passing down through the well to the bottomof the tubing and up the tubing string, driving the tool `ahead of it upthe tubing -to the top of the well. Alternatively, a wire line with afishing head may be lowered into the well to connect with the top `ofthe tool and later remove it from the well by pulling it upwardly by thewire line, in a manner Well known to the art. Various methods ofintroducing and removing objects from a well are described in U.S.Patents 2,805,718 issued September 10, 1957, and 2,810,442 issuedOctober 22 1957 to G. H. Tausch.

One drawback with the method of circulating a well tool or other pieceof equipment in and out of a well is that the packer or sealing elementcarried `by the tool, or lby any retrieving tool sent to latch on to awell tool7 is subject to wear due to the trictional contact between thesealing element and the inside Wall of the tubing string. Thus it lmaybe readily seen that if a tool and its packer is circulated to thebottom of -a 10,000-foot well, considerable wear may take place on thepacker so that by `the time the tool and the packer reaches the bottomor the well there is no longer a perfect seal between the packer and theinside wall of the tubing string. This is especially true in the eventthat a tubing string is used having upset ends with exposed threads or asmall space between adjacent sections of the inner wall. Destruction ofthe seal between the packer and the tubing wall makes it dihcult if notimpossible later to circulate the packer and its tool upwardly to thetop of the well. Addition-ally, without a perfect seal between thepacker and the tubing wall at all times, it is impossible to determinethe position of the tool in the Well during either its upward orrdownward travel. On the other hand, with a perfect seal between apacker and the tubing wall, the position of a tool or instrument beingcirculated down the well may be known at any time `by measuring thenumber of gallons of driving ilnid being pumped into the well to forcethe packer and its tool or instrument one direction or the other.

1t is therefore a primary object of the present invention to provide anapparatus for moving a tool, instrument or other object to apredetermined position within a pipe.

Another object of this invention is to provide an apparatus for moving atool, instrument or other object through a pipe while at the same timemaintaining a perfect seal within the pipe at all times.

A further object of the present invention is to provide `an apparatusincluding sealing means which are designed to maintain a perfect sealwithin a pipe when passing therethrough, with means for by-passing fluidthrough said apparatus when it is seated in the pipe.

Still another object of this invention is to provide an apparatus havingdual sets or" sealing means adapted to be selectively actuated whenbeing run in a well, so that a different sealing element is used whenthe apparatus is run in opposite directions.

A still further object of this invention is` to provide a iiexible toolcarrier adapted to pass around bends in a pipe, said carrier beingprovided with selectively inllatable sealing elements, at least one ofwhich is inated to maintain an effective seal within a tubing string asthe tool carrier is pumped therethrough, with the seals being spaced onthe tool carrier to span any recess in the tubing string.

These and other objects of this invention Will be understood from thefollowing description with reference to the drawing, wherein FIGURES 1to 6 are diagrammatical views taken partially in longitudinalcross-section of different forms of a tool carrier or tool pusher inaccordance with the present invention.

Referring to FIGURE 1 of the drawing, a tool carrier constructedaccording to the present invention is shown positioned in a verticalsection of tubing such as employed in an oil well. The tool carriercomprises a central mandrel 11 on which are mounted a pair of sealingelements or packers 12 and 13 which surround the central mandrel 11 andare held thereon by suitable sealing-element or packer-retaining cups orrings 14 and 15, 16 and 17, respectively. The sealing elements 12 and 13and their retaining cups 14, 15, 16, and 1'7 are held in position on themandrel 11 by retaining nuts 13 and 19.

Preferably the mandrel 11 is provided with a flexible linkage such as aball-and-socket joint 21 at a point between the sealing elements 12 and13 so as to facilitate movement of the tool carrier in `curved sectionsof a well tubing or pipe. Since the possibility always exists that anytool attached to the tool carrier may become stuck in a well, the toolcarrier is preferably provided with a shing head 22 whereby a retrievingtool (not shown) attached to the bottom of a wire line may be loweredthrough the tubing string 16 to latch onto the fishing head 22, therebyallowing removal of the tool carrier by an upward pull on the Wire line.

As illustrated, the packer retaining elements or cups 14 and 1S surroundthe ends of the packer or Sealing element 12 while at the same timebeing axially spaced from each lother on the central mandrel 11 so thatthe packer element 12 is against, or may be expanded against, the innerwall of the tubing 10 to form a seal thereagainst. Preferably, thesealing elements 12 and 13 are formed having an internal diameterslightly larger than that of the mandrel 11 so that an undercut portionor annular space 23 is for-med between the mandrel and the sealingelement 12.

Fluid ports 24 and 25 Aare provided through the walls of the packerretaining cups 15 and 17 near the closed ends thereof so that fluidpassageways are formed through the packer retaining cups incommunication between the space outside the packer and the annular space23. Since the sealing element 12 of FIGURE -l may during use be causedto rotate slightly with regard to its retaining cups 14 and 1S, it ispreferably [designed so that the closed end of the cup terminates aboveport 24 so that the fluid passageway is maintained at all times incommunication between the inside of the sealing element 12 and the spaceoutside the tool carrier. Sealing element 13 may also rotate during usein a similar manner.

The packers or sealing elements 12 and 13 are made of any suitableinflatable resilient material such as rubber, synthetic rubber,rubberized fabrics or certain plastic materials which may be expandedunder the application of uid pressure. The portion of the sealingelement 12 in contact with the inner wall of the tubing 1t) may have athickened cross-section so as to provide for some wear on the seal as itis propelled through the tubing. In addition, the sealing element 12 maybe bevelled to substantially a point, as illustrated, ir" desired.

Preferably, the sealing element 12 is formed so that its lower end,i.e., the end farthest yfrom iluid port 24, fits closely about thecentral mandrel 11 near the lower yretaining cup 14 in a fluidtightmanner. In the event that the packer 12 does not have a tight fit atthis point, an O-ring seal 26 may be positioned between the retainingcup 14 and the mandrel 11.

When the tool carrier of the present invention is to be used to run atool or instrument down a well tubing 11i, the present tool carrier orpusher may merely be in touching engagement with the tool to beinserted, or alternatively may be xedly secured to the tool in 'anysuitable manner as by screw threads or, if desired, detachably connectedby spring Iclips or other readily detachable latching means. In runninga tool to the bottom of a well the tool would first be inserted in thetop of the owline and tubing with the present tool carrier forced inbehind it. The top of the tubing would then be closed and uid pressurewould be applied to drive the tool and its tool carrier down to thebottom of the well. When pressure is applied above the tool carrierillustrated in FIGURE l, the pressure fluid llows past sealing element13 and enters fluid ports 24 and 25 leading to the sealing elements 12and 13, respectively. Since the fluid prwsure on either side of thebevelled sealing element 13 would be the same there would be no tendencyfor the sealing element 13 to expand against the wall of the tubing toform a fluidtight seal thereagainst.

rIlhe pressure fluid entering fluid port 211 would pass down into theannular space 23 and force the sealing element 12 against the inner wallof the tubular member 1t) so that the lower sealing clement 12 would actas a piston to be forced `downwardly through the tubing string 1@ by theapplication of further pressure iluid above it. This action takes placesince a useable pressure differential exists yacross the lower sealingelement 12 of FIGURE l whereas no useable pressure diiferential existsacross the sealing element 13 on downward travel of the tool carrier.'Ihus it may be seen that, on the downward travel of the present toolcarrier, the upper sealing element 13 would merely be a follower-pistonwhich would not contact the tubing wall with any force to form a sealthereagainst and hence would not be subject to wear as the tool carrierpasses downwardly through the tubing string 10. With the lower packer 12maintaining `a tight tit in ythe tubing string 10 at all times, theprecise location of the tool carrier or pusher can be determinedaccurately at any time from a measure of the amount of pressure uidinjected or pumped into the top of the tubing string 10.

To return the tool carrier, with -or without its accompanying tool (notshown), circulation `of the driving fluid in the well is reversed sothat the pressure fluid would pass downwardly outside the tubing string10 and upwardly through it. Thus the action of the sealing elements 12and 13 would be reversed with sealing element 13 acting as the piston,and sealing lelement 12 acting as the follower.

In the event that the tool `carrier is sent down to the bottom of thewell to retrieve a tool, instrument, or other object therein, the toolcarrier is provided with suitable latching means 27, well known to theart, which may take the form of the one described in US. Patent1,700,324 issued January 29, 1929, and `entitled Letting-In Tool for Oiland Gas Well Appliances. This latching device 27 would normally be xedlysecured to the central mandrel 11 in any suitable manner, as by screwthreads. Thus upon circulating the present tool carrier downwardly tothe bottom of a tubing string it would latch on to the top of the tool,instrument, or other object therein and, upon reversing the circulationof the fluid in the well would pull the tool or other object upwardlywith it when the tool carrier was circulated to the surface.

While the present tool carrier has been illustrated as having a sealingelement 12 acting as a leading piston with a follower uninated sealingelement behind it, it is realized that the sealing elements of the toolcarrier could be turned end to end as illustrated in FIGURE 2, in whichcase the sealing element 13a first exposed to upstream pressure wouldserve as the piston which would push ahead of it the uninflated sealingelement 12a on the downward trip into the Well. On the upward trip theactions would be reversed with the lower packer 12a acting as the pistonand pushing ahead of it the upper sealing element 13a. It is essentialthat one of the fluid ports, say port 25a, of one sealing element 13a bepositioned on the downstream side thereof when positioned within theflow stream within a pipe, while port 24a of the other sealing elementis positioned upstream. In this case the fluid pressure is considered asbeing applied upwardly through the tubing 10.

An alternative arrangement of the present tool is shown in FIGURE 3 withparts similar to those of FIG- URE 1, the main dilference being that thetool of FIG- URE 3 is not provided with a fishing head 22 or latchingmeans 27, as shown in FIGURE 1. In this arrangement the packers 12b and13b are mounted on tubular mandrels 11b and 9b, respectively. The endsof the packers or sealing elements 12b and 13b are held firmly in placeby the retaining cups 14b, 15b, 16b, and 1711. The space 23b is incommunication with the space outside the packer 12b through port 24h,bore 28h and port 29b. It is evident from the construction of the toolof FIG- URE 3 that, in the absence of any means for attaching thepresent apparatus to a tool or instrument, etc., the present apparatuscan only be used to push a tool, instrument, etc., into place.

The arrangement shown in FIGURE 4 of the drawing is merely one-half ofthe apparatus shown in FIGURE 3 without the swivel joint 2lb of FIGURE3. This tool may be employed as a one-way pumpable barrier, in the eventthat it is not desirable to return the apparatus to its starting point.It is essential that all of the packers 12, 12b, `and `12e be firmlysecured at their ends by means of retaining cups which prevent thepressure of the fluid stream from opening the packer up to an extentsuch that the flexible packer member 12C is caused to turn inside out.Thus in many present tools, an unrestrained swab cup arrangement isundependable because the edges of the cups, facing the direction inwhich the device is to be moved, often catch on the irregularities inthe pipe wall, for example in the pipe joints, and furthermore the edgesare often folded back over their sides where they are quickly damaged toa point of being inoperable.

Field operations with the present apparatus has established that it isuseful in at least two types of tube cleaning operations for removingsolids adhering to the interior of a pipe string positioned within anoil well. The present apparatus can be effectively used in removingparain from Well tubing. In pumping `the present apparatus down aparaflindaden production string, most of the paraffin is pushed ahead ofthe apparatus into the heated zone near the well bottom where theparaffin is melted and re-entrained in the Well production fluid. Onreturn of the present apparatus to the top of the well, by circulationin a manner herein described above, additional portions of the thin ilmof paraflin left on the interior wall of the tubing are pushed ahead ofthe present apparatus, and the warm para'in entrained in the fluidimmediately behind the present apparatus is moved through the tubing ina manner which inhibits or reduces the redeposition of solid parafn inthe cooler regions traversed by the tubing string.

The present apparatus can be similarly eifective in removing hydrocarbonplugs which tend to form in tubing strings and ilowline in whichproduction fluids from high gas ratio wells are conveyed through Zonesin which the temperatures are low relative to that of the producedfluid. The formation of these rather complex hydrocarbon solids is ananticipated problem in underwater wells in which the production tubingstring and flowline are exposed to ocean floor temperatures in the orderof to F.

The present apparatus is also particularly useful in insurinig that aselected portion of a pipestring is contacted by the treating fluid,such as a corrosion inhibitor or a solvent. In field operations it hasbeen established that the slippage of the driving tluid past the presenttype of barriers is extremely small. For example, the metering of theamount of iluid used in pumping the barrier along the pipe stringprovides an accurate prediction of the time of arrival of the tube at astop or a sharp bend which has a known location and produces a knownfluctuation in the fluid pressure. Since the slippage of iiuid past thepresent apparatus is minor when a volume of treating fluid is introducedinto a pipe string ahead of the present type of barrier and both arepumped to the bottom of a pipe string, the treatment of the entirelength of pipe string can be definitely established. A barrier inaccordance with the present invention can be left in the tubing stringto be circulated out by the production Huid of the Well or can Ibeimmediately removed by pumping the fluid through the pipe string in theopposite direction. If a single barrier in accordance with FIGURE 4 isto be employed, it is essential that the length of the barrier or itsmandrel lllc be greater than the inside diameter of the pipeline throughwhich it is to be pumped so that the barrier will not tilt within thepipe and lose its seal. In the case of a single barrier as shown inFIGURE 4 it is essential that the shape of the packer iZc and the length,t

of the central mandrel ille be such that a seal is maintained at alltimes with the pipe Wall.

In order to carry out many operations within a well, each section of themandrel Il (FIGURE 1) is provided with a fluid passageway, preferably inthe form of central bores 30 and 36a which are in communication witheach other through a fluid passageway 3l in the ball-andsocket joint 2l.The upper end of the fluid passageway 30a communicates with the spaceoutside the tool carrier through a flow passage 32 in the tishing neck22. The ow passage 32 is normally closed by a spring-loaded check valve33 or any other suitable pressure-responsive valve which is set to openat a pressure higher than that needed to propel the present tool carrierthrough a string of tubing under iiuid pressure. The lower end of thebore 30 is in communication with the interior of the well tubing l@below the tool carrier through the latching device or tool connection27.

In one type of a well operation, the latching element 27 may bereleasably connect to a device or piece of apparatus to be run into andleft in a pipe or tubing itl. By pumping fluid down the tubing lil abovethe tool carrier, as described hereinabove with regard to FIGURE 1, thetool carrier is pushed down the tubing to a predetermined seatingposition, such as a seating shoulder 34.

rllhe pressure in the tubing I1 above the tool carrier is increasedsutiiciently to open valve 33 and allow iiuid to be pumped against atool (not shown) carried by the latching mechanism 27 to force the toolout of the latching mechanism and allow it to drop or be positioned in apredetermined seating position or recess in the tubing 10. By reversingcirculation in the tubing 1G, the tool carrier is then pumped to the topof the well again.

In certain pipe or tubing strings used in an oil and/or gas well, aportion of the bore of a tubing or casing string 4% is enlarged toreceive or seat a certain well tool or device. An example of this is theentrance 41 formed in the Wall of a pipe string 4G to permit a gas liftvalve (not shown) to be seated in a housing 42 secured to o1' formed onthe outer wall of the tubing 4t). ln using the tool carrier of thepresent invention, a recess at any point with a tubing string 40 whichenlarges the cross-sectional flow area often provides a place where thetool carrier could hang up. This is due to the fact that when it is insuch a recess, the fluid stream propelling the tool carrier down thetubing may pass around the sealing element, say 13, and not exertsufficient pressure on the tool carrier to propel it through the tubing.This is especially true when circulation of iluid is in an upwarddirection to pump a tool carrier and a heavy tool connected thereto outof the well.

In FIGURES 5 and 6 of the drawing, tool carriers are illustrated showingpreferred arrangements of the packers in order to insure continuedsealing of at least one packer against the inner wall of the tubing 4i)at all times. In FIGURE 5 two pairs of packer elements are arranged intandem with the two packers 43 and 44, which are responsive to downwardpressure mounted alternatingly with two other packers 45 and 46 whichare responsive to upward fluid pressure. The spacing between any twopackers d3 and 44, or 45 and 46, in one direction is at least slightlygreater than the recess 41 in the wall of the tubing liti. This spacingis important and must be adhered to when the packers are arranged in themanner illustrated in FIGURE 6 with two similarly directed packers 43and 44 mounted above oppositely directed packers 415 and 46.

This application is a continuation-impart of copending patentapplication Serial No. 807,708, tiled April 20, 1959.

I claim as my invention:

l. Apparatus adapted to be pumped through a pipe, said apparatuscomprising a body mandrel element of a diameter smaller and a lengthlonger than the diameter of the pipe through which it is to be pumped inan unsupported manner, expandible annular sealing means carriedco-axially on said mandrel element, retaining means fixedly securingopposite ends of the sealing means to said body mandrel element, luidpassage means in said apparatus in communication between the inside ofsaid sealing means and the outside of said apparatus near one endthereof, a central flow passageway through said body element, andpressure-responsive valve means normally closing said flow passageway.

2. Apparatus adapted to be pumped through a pipe, said apparatuscomprising a body mandrel element of a diameter smaller .than the pipestring through which it is to be pumped in an unsupported manner, atleast a pair of selectively expandible annular sealing means carried onsaid mandrel element in axially spaced relationship and arranged toexpand one at a time, fluid passage means in said apparatus adjacenteach of said sealing means in communication between the inside andoutside thereof, the opening of said iiuid passage means of one sealingmeans being positioned on the upstream side thereof when positioned in aiiow stream within a pipe, while that of the other sealing means ispositioned on the down stream side thereof, a central iiow passagewaythrough said body mandrel element, and pressure-responsive Valve meansnormally closing said flow passageway, said valve 7. means beingadjusted to open at a pressure greater than that needed to expand saidannular sealing means.

3. Apparatus adapted to be pumped through a pipe, said apparatuscomprising a body mandrel element of a diameter smaller than the pipestring through which it is to be pumped in an unsupported manner, atleast a pair of selectively expandible annular sealing means carried onsaid mandrel element in axially spaced relationship and arranged toexpand one at a time, tluid passage means adjacent one end of each ofsaid sealing means in communication between the inside and outsidethereof, the opening of said fluid passage means of one sealing meansbeing positioned on the upstream side thereof when positioned in a flowstream within a pipe, while that of the other sealing means ispositioned on the downstream side thereof, flexible joint means in saidmandrel element between said pair of sealing means, a central flowpassageway through said body mandrel element, and pressureresponsivevalve means normally closing said flow passageway, said valve meansbeing adjusted to open at a pressure greater than that needed to expandsaid annular sealing means.

4. Apparatus adapted to pump an object through a pipe, said apparatuslcomprising a body mandrel element of a diameter smaller than the pipestring through which it is to be pumped in an unsupported manner, atleast a pair of selectively expandible annular sealing means carried onsaid mandrel element in axially spaced relationship and arranged toexpand one at a time, fluid passage means in said apparatus adjacent oneend of each of said sealing means in communication between the insideand outside thereof, the opening of said tluid passage means of onesealing means being positioned on the upstream side thereof whenpositioned in a ow stream within a pipe, while that of the other sealingmeans is positioned on the downstream side thereof, flexible joint meansin said mandrel element between said pair off sealing means, connectingmeans at one end of said mandrel element for connecting said mandrel toanother object within said pipe, a central ow passageway through saidbody mandrel element, and pressure-responsive valve means normallyclosing said flow passageway, said valve means being adjusted to open ata pressure greater than that needed to expand said annular sealingmeans.

5. Apparatus ladapted to pump an object through a pipe, said apparatuscomprising a Ibody mandrel element of a diameter smaller than the pipestring through which it is to be pumped in an unsupported manner, atleast a pair of selectively eXpandible annular sealing means carried onsaid mandrel element in axially spaced relationship and 'arranged toexpand one at a time, iluid passage means in said apparatus adjacent oneend of each of said sealing means in communication between the insideand outside thereof, the opening of said fluid passage means of onesealing means being positioned on the upstream side thereof whenpositioned in a flow stream within a pipe, while that of the othersealing means is positioned on the downstream side thereof, llexiblejoint means in said mandrel element between said pair of sealing means,connecting means at one end of said mandrel element for connecting saidmandrel to another object within said pipe, a fishing head secured tothe other end of said mandrel element, a central flow passageway throughsaid body mandrel element, and pressureresponsive Valve means normallyclosing said flow passageway, said valve means being adjusted to open ata pressure greater than that needed to eXp-and said annular sealingmeans.

6. Apparatus adapted to pump an object through a pipe, said apparatuscomprising a body mandrel element of a diameter smaller than the pipestring through which it is to be pumped in an unsupported manner, atleast a pair of selectively expandible annular sealing means carried onsaid mandrel element in axially spaced relationship arranged to expandone at a time, each of said sealing means having a portion thickened incross-section adapted to contact the inner wall of said pipe string, uidpassage means in said apparatus adjacent one end of each of said sealingmeans in communication between the inside and outside thereof, theopening of said fluid passage means of one sealing means beingpositioned on the upstream side thereof when positioned in a ow streamwithin a pipe, while that of the other sealing means is positioned onthe downstream side thereof, exible joint means in said mandrel elementbetween ysaid pair of sealing means, connecting means at one end of saidmandrel element for connecting said mandrel to another object withinsaid pipe, a fishing head secured to the other end of said mandrelelement, a central flow passageway through said body mandrel element,and pressure-responsive valve means normally closing said flowpassageway, said valve means being adjusted -to open at a pressuregreater than that needed to expand said annular sealing means.

References Cited in the le of this patent UNlTED STATES PATENTS 971,042Hill et al. Sept. 27, 1910 2,000,109 Tyler May 7, 1935 2,221,775 BoyntonNov. 19, 1940 2,764,244 Page Sept. 25, 1956 2,785,757 Middleton Mar. 19,1957

